'Money laundering'

There have been issues around the digital currency, including a lack of regulation and concerns over potential for money laundering and other illegal activity.

In October 2013 the FBI shut down online marketplace Silk Road, which traded in drugs and other illegal goods and took payments using "crypto-currencies".

"There is an anonymity associated with Bitcoin... but any cash or any Bitcoin coming into or out of our fund has to be fully identified under KYC (Know Your Customer) procedures, so there will be no dictators or criminals sending us money," said Mr Masters.

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Bitcoin payments work by sending money from one wallet directly to another